Upright piano action



Patented Feb. `16, 1926.

i UNITED STATES JOSEPH HMPEL, OF WEST HAVEN, CONNECTICUT.

UPRIGHT PIANG ACTON.

Application flid March 2.9, 1923.

To all to hof/'a if 91mg/ concern.:

Be it known that I, Josemi' IIurrnn, a citizen 'ot the United States, residing at 55'? First Avenue, `illest Haven. in the county ot New Haven and State of Connecticut, have invented a new and useful In'iprov'ement in an Upright Piano vfiction, o't which the tollowing` is a specification.

My invention has reference, in its broad aspect, to improvements in hammer checking devices tor upright piano actions, and nore particularly it is my purpose to pro vide means in the :term ot a check block carried by the hammer-butt 'for coaction with a lug on the liack ot an action unit whereby complete retraction o'tl the hammer Ot the unit, after it has delivered a blow, is interrupted until the piano key is completely released. Furthermore, I have pr0- vided in conjunction with my aforementioned improved hammer check a unique adjusting device for effecting accurate alignment oit the hammer with other hammers.

Another and equally important object of my invention is to provide a hammer check formed with an uninterrupted curved itacc for both wiping and positive engagement with a correspondingly curved tace et the lug on the 'jack whereby to 'facilitate the action ot' the hammer check* and it is also my purpose to attain by the use of my check the elimination ot the usual bridle, bridle wire, back check, back check -telts and back check tapes which have heretofore lent to the complexity ot piano actions. ol" this type.

The particular' elements ol my check device employed to accomplish the above and other equally important objects will be hereinatter more fully described in detail and specilically pointed out in the claim appended hereunto and forming a part ot this specification.

In the accompanying drawings wherein is illustrated the preferred embodiment of my invention Figure 1 is a vertical section o'l" a conventional single action unit showing my device applied thereto, and

Figure 2 is a perspective view ot my invention per se.

Like characters of reference refer to like or similar parts throughout the several views of the drawings, in which For the purpose of properly disclosing the construction and arrangement ot' the elements of my hammer check and adjusting Serial No. 626,223.

device, I have shown the details ot a conventional action unit ot' an upright piano which consists essentially in trame element-s (l a ke;Y (2), and a riser (3) pivotally connected with a jack lever (il) which is car ried by the usual action rail Pivoted` to the jack lever is a jack (6) formed with a spring pressed heel (7), and limited in movement by the adjustable fixed stop (Tu). Also pivoted to the action rail (5) is a humilier-butt (8) carrying the hammer (9), which in its norma-l inactive position rests upon the hammer rest rail (10) carried by the trame fr piano string is shown at (11), and is engaged by the imite (12). Suitable action springs (13) and (14e) are provided viter an obvious purpose-one operatingl upon the hammer, and the other upon the mute. All ot the above deiined structurc'is conventional and forms no part ot my invention.

My invention per se has to do with checking the retraction oit' the hammer (9) after a blow is struck and before the key (2) is completely released, and in adjusting the alignment ot the hammer, with other hammers (not shown). In order to accomplish these ends I have mounted upon the hamJ mer-butt (S) a shatt (15) which extends substantially at right angles to the hammer sha tt and carries a head (16) which eX- tends toward and in proximity with the jack (G) and substantially parallel with the hammer sha'lt. 'lhe body portion (17) ot the head (16) has a curved uninterrupted tace (1S) which is adapted to engage a lug (19) Yformed on the upper cud of the jack (S). The lug (19) is provided with a curved, uninterrupted tace (20) cooperating` with the tace (1S) whereby to attain a positive as well as a slight wipingl engagement therebetween to facilitate the accomplishment ot the purposes of my invention. In action, when the hammer (9) is thrown against the string (11) by a blow 'from the jack (6) the body (17) engages the lug (19) upon the return to interrupt retraction ot the hammer until the key is completely released. This permits of the rapid and successive striking o't light blows with the hammer as retraction is prevented until the key is completely released, and the hammer maintained at about three-'fourths oit an inch trom the string between blows thereupon. Then the key is completely released the hammer moves to a position of rest against the hammer' rest rail (10) under the influence of the Weight of the hammer, the mpulse exerted by the string, and the Weight of the check.

As is clearly illustrated in Figure 2, the head (16) is cut-away as at (21), and seated Within said cut-away portion is a block (22), formed with a elted head, and carried by an adjusting screw (23) journalled in the head (16). Thus by turning the screw the block is advanced or retracted Within the cutaway portion (21). A perfect alignment of the hammer may be secured by striking the keys, and after the hammers have fallen back into the position assumed before the keys are released, adjusting the blocks (22) so that they raise or lower the hammers into the position desired by engagement with the lug 19 of the jack The block (22) serves a double rle in that it not only makes possible a perfect alignment of the hammers but it insures a perfect catch by the head (16) of the lug rupted face, a check device includingy a head y carried by the hammer-butt and formed with a curved depending body forming a pocket for the lug, and a block adjustably carried by the head and movable to engage the lug' in a direction at approximately right angles to the vertical axis of the jack for regulating' the position of the hammer.

JOSEPH HIM PEL. 

